Semiconductor device with lead terminals having portions thereof extending obliquely

ABSTRACT

A semiconductor device includes a semiconductor chip and a plurality of leads. The leads include a first lead including a supporting portion for mounting the semiconductor chip, and a projecting portion which projects in a first direction from the supporting portion. A second lead extends in a second direction non-parallel with the first direction, and one or more third leads extends in the second direction, such that a line extending in a third direction perpendicular to the first direction passes through the second lead and the one or more third leads. The second lead includes a first portion and a second portion, the first portion having a width larger than the second portion, the first portion having one side parallel to the first direction, and the first portion located between the second portion and the first lead.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of copending application Ser. No.15/794,159, filed on Oct. 26, 2017, which is a continuation ofapplication Ser. No. 15/272,557, filed on Sep. 22, 2016 (now U.S. Pat.No. 9,812,382, issued on Nov. 7, 2017), which is a continuation ofapplication Ser. No. 14/716,238, filed on May 19, 2015 (now U.S. Pat.No. 9,472,492, issued on Oct. 18, 2016), which is a continuation ofapplication Ser. No. 14/132,019, filed on Dec. 18, 2013 (now U.S. Pat.No. 9,064,855, issued on Jun. 23, 2015), which is a continuation ofapplication Ser. No. 13/832,377, filed on Mar. 15, 2013 (now U.S. Pat.No. 8,637,976, issued on Jan. 28, 2014), which is a continuation ofapplication Ser. No. 13/223,364, filed on Sep. 1, 2011 (now U.S. Pat.No. 8,421,209, issued on Apr. 16, 2013), which is a continuation ofapplication Ser. No. 12/659,733, filed on Mar. 19, 2010 (now U.S. Pat.No. 8,026,591, issued on Sep. 27, 2011), which is a continuation ofapplication Ser. No. 10/795,247, filed on Mar. 9, 2004 (now U.S. Pat.No. 7,705,444, issued on Apr. 27, 2010), which is a divisional ofapplication Ser. No. 09/970,056, filed on Oct. 4, 2001 (now U.S. Pat.No. 6,710,431, issued on Mar. 23, 2004). Furthermore, this applicationclaims the benefit of priority of Japanese application 2000-307377,filed on Oct. 6, 2000. The disclosures of these prior U.S. and Japaneseapplications are incorporated herein by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a resin-sealed type semiconductordevice, and especially to a one-side resin-sealed type semiconductordevice in which a surface of a lead frame on which a semiconductorelement is mounted is sealed with a resin and a lead frame usedtherefor.

Description of Related Art

Resin-sealed type semiconductor devices each provided with a lead framefor electrically connecting electrodes of the semiconductor to an outerwiring and the like are widely used. In such a semiconductor device, alead frame generally comprises a supporting portion for mounting asemiconductor element thereon, hanging lead portions for supporting thesupporting portion, and lead terminal portions for connecting metalwires thereto. A lead frame used in the process of fabricatingsemiconductors includes a plurality of unit regions corresponding to aplurality of semiconductor devices so that the plurality ofsemiconductor devices can be fabricated at the same time. One unitregion has a substantially rectangular shape. Each of the hanging leadportions extends inwardly from a corner portion of this rectangle, andin many cases, the lead terminal portions extend inwardly from sideparts of the unit region.

FIG. 5 is an enlarged schematic pan view showing a part in the vicinityof a corner of a unit region.

In the central part of the substantially rectangular unit region (in thedirection of arrow G), a supporting portion 51 is disposed. A hanginglead portion 52 extends from the supporting portion 51 toward the cornerportion. In the side parts of the unit region, substantially rectangularlead terminal portions 53 are provided. Base end portions of the leadterminal portions 53 are connected to a peripheral frame part 50. Thelongitudinal direction of the hanging lead portion 52 and thelongitudinal direction of the lead terminal portion 53 makes an angle ofsubstantially 45°.

In a lead frame, a plurality of unit regions each having such astructure are arranged and connected to the frame part 50. In theprocess of fabricating semiconductor devices, a lead frame is sealedwith a sealing resin in such a manner that the bottom surface of thelead terminal portion 53 is exposed. Thereafter, each unit of lead frameis cut along a cutting line M shown in broken line, and the cut end faceis substantially in the same plane with the side surface of the sealingresin.

In order to obtain a small-sized semiconductor device, it is preferablethat the length of the lead terminal portion 53 is as short as possible.However, since the lead terminal portion 53 functions as a lead forconnection with outer wiring substrate, the lead terminal portion 53needs to have a length (area) more than a predetermined length (area).From these reasons, the lead terminal portion 53 is formed to have apredetermined necessary minimum length L1.

The minimum distance between the hanging lead portion 53 and the leadterminal portion 53A adjacent to the hanging lead portion 53 must belarge enough to ensure insulating reliability between them. However, inorder to obtain a small-sized semiconductor device, it is preferablethat the minimum distance between them is small. From these reasons, theminimum distance between them is designed to be a predeterminednecessary minimum distance L2.

However, since the predetermined length L1 and the predetermine distanceL2 are required to be secured, miniaturization of mounting area of asemiconductor device is limited.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a semiconductor devicein which each lead terminal portion has a length (area) necessary forouter connection and at has a length (area) necessary for outerconnection and at the same time insulating reliability between thehanging lead portions and lead terminal portions is secured, and a leadframe used for the semiconductor device.

Another object of the present invention is to provide a semiconductordevice having a small mounting area, and a lead frame used for thesemiconductor device.

In one embodiment, a semiconductor device includes a semiconductor chiphaving a plurality of electrodes on a first surface thereof and aplurality of leads. A first lead has a supporting portion for mounting asemiconductor chip thereon and a projecting portion which projects in afirst direction from the supporting portion. A second lead extends in asecond direction non-parallel with the first direction, and one or morethird leads extends in the second direction, such that a line extendingin a third direction perpendicular to the first direction passes throughthe second lead and the one or more third leads. A plurality of wiresconnects the plurality of electrodes with the second lead and the one ormore third leads. Resin covers the semiconductor chip, the first lead,the second lead, the plurality of third leads, and the plurality ofwires. The second lead has a first surface and a side surface, such thatone of the plurality of wires is connected to the second lead on thefirst surface. The second lead includes a first portion and a secondportion, the first portion having a width larger than the secondportion, the first portion having one side parallel to the firstdirection, and the first portion located between the second portion andthe first lead. The side surface of the second lead is exposed from theresin and is co-planar with an outer surface of the resin. The one ormore third leads each includes a first portion, a second portion, and athird portion, such that the first portion is located between the secondportion and the third portion and has a width greater than the secondportion and the third portion. The one or more third leads each includesa first surface and a side surface, such that one of the plurality ofwires is connected to the one or more third leads on the first surface.The side surface of the third lead is exposed from the resin and isco-planar with an outer surface of the resin.

In one embodiment, the one or more third leads includes a plurality ofthird leads arranged such that a line parallel to the second directionintersects each of the plurality of third leads.

A width in the second direction of the supporting portion of the firstlead may be greater than a width in the second direction of the secondlead, and a width in the third direction of the supporting portion ofthe first lead may be greater than a width in the third direction of thesecond lead.

In one embodiment, the one or more third leads includes a first row of aplurality of third leads arranged in the second direction and a secondrow of a plurality of third leads arranged in the third direction, awidth in the second direction of the supporting portion of the firstlead is greater than a width in the second direction of the first row ofthird leads, and a width in the third direction of the supportingportion of the first lead is greater than a width in the third directionof the second row of third leads.

In one embodiment, the second lead includes four pairs of second leadsarranged at corners of the supporting portion of the first lead. Eachsecond lead of each pair of second leads may be configured such that theone side of the first portion parallel to the first direction isparallel to the one side of the first portion of the other second leadof the pair of second leads and faces the one side of the first portionof the other second lead of the pair of second leads.

In one embodiment, the one or more third leads includes a second surfaceopposite the first surface, the first surface of the first portion ofthe one or more third leads having a width greater than the secondsurface of the first portion of the one or more third leads.

In one embodiment, the first surface of the second portion of the one ormore third leads has a width equal to the second surface of the secondportion of the one or more third leads.

The first portion of the one or more third leads may have a trapezoidalcross-sectional shape.

In one embodiment, the one or more third leads includes first, second,third, and fourth rows of a plurality of third leads, the first andsecond rows of third leads are symmetrical with respect to the seconddirection, and wherein the third and fourth rows of third leads aresymmetrical with respect to the third direction

According to one embodiment, a semiconductor device according to thepresent invention comprises a semiconductor chip having electrodes onthe surface thereof, a lead frame having a plurality of lead terminalportions for electric connection and a plurality of hanging leadportions each extending obliquely with respect to the lead terminalportions and supporting a supporting portion on which the semiconductorchip is mounted, metal wires for connecting the lead terminal portionsand the electrodes of the semiconductor device, and a sealing resin forsealing the semiconductor element, the lead frame and the metal wires insuch a manner that a part of each lead terminal portion is exposed. Theplurality of lead terminal portions include chamfered lead terminalportions each having, at its head, a chamfered portion formedsubstantially in parallel with the hanging lead portion so as to avoidinterference with the hanging lead portion.

Further, a lead frame according to the present invention comprises aplurality of lead terminal portions for electric connection and aplurality of hanging lead portions each extending obliquely with respectto the lead terminal portions and supporting a supporting portion onwhich the semiconductor chip is mounted. The plurality of lead terminalportions include chamfered lead terminal portions each having, at itshead, a chamfered portion formed substantially in parallel with thehanging lead portion so as to avoid interference with the hanging leadportion.

According to this invention, the lead terminal portions are chamferedsubstantially in parallel with the hanging lead portion so as to avoidinterference with the hanging lead portions. Accordingly, even if thechamfered lead terminal portion is disposed nearer to the hanging leadportion in comparison with the case of the conventional lead terminalportion, a distance more than a predetermined distance can still besecured between the lead terminal portion and the hanging lead portion.

That is, in a conventional lead frame, a lead terminal portion has acorner portion protruding toward a hanging lead portion. Therefore, ithas been necessary to dispose the lead terminal portion substantially onthe peripheral part side in order to avoid interference between an edgeof the corner portion and the hanging lead portion and secure a distancemore than a predetermined value therebetween. As a result, a unit regionin a lead frame corresponding to a semiconductor becomes large, and thesize in the plane direction of a semiconductor device using this unitregion becomes large.

On the contrary, according to the present invention, the lead terminalportion has a chamfered portion at its head and is opposed to thehanging lead portion at this chamfered portion. Therefore, the hanginglead portion can be disposed at a more inner portion in comparison withthe case of the conventional structure. Accordingly, a unit region oflead frame can be small-sized. As a result, the size in the planedirection of a semiconductor device can be reduced and the mounting areaof the same can be also reduced.

The chamfered portion is preferably comprises a linear side in parallelwith the lateral side of the hanging lead portion. However, other shapesare similarly effective as long as the portion is chamfered so as toavoid interference by the hanging lead portion. For example, thechamfered portion may comprise a curved side. Further, in the chamferedportion, the oblique side may extend through only a part or the wholewidth of the lead terminal portion.

It is preferable that the abovementioned chamfered lead terminal portionis disposed adjacent to the hanging lead portion.

Not only the lead terminal portion adjacent to the hanging lead portionbut also another lead terminal portion adjacent to this chamfered leadterminal portion maybe a chamfered lead terminal portion. However, inthis case, the chamfered lead terminal portion adjacent to the hanginglead portion becomes shorter than the other chamfered lead terminalportions. Therefore, it is preferable that only lead terminal portionsadjacent to the hanging lead portion have such a chamfered portion. Inthis case, there is no remarkably short lead terminal portion.Therefore, in a semiconductor device using such a lead frame, all thelead terminal portions can be suitably connected to metal wires and anouter wiring substrate.

When only each lead terminal portion adjacent to the hanging leadportion comprises a chamfered lead terminal portion, the chamferedportion preferably has an oblique side extending throughout the wholewidth of the lead terminal portion. Thereby a unit region of lead framecan be minimized and the size of a semiconductor device using the samecan be minimized in plan view. The foregoing and other objects,features, aspects and advantages of the present invention will becomemore apparent from the following detailed description of the presentinvention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view showing a unit region of lead frameaccording to an embodiment of the present invention.

FIG. 2 is an enlarged schematic plan view showing a part in the vicinityof a corner of the unit region of lead frame shown in FIG. 1.

FIG. 3A is a sectional view along a cutting line C-C in FIG. 2, and FIG.3B is a sectional view along a cutting line D-D in FIG. 2.

FIG. 4 is a schematic sectional view of a resin-sealed typesemiconductor device fabricated using the lead frame shown in FIG. 1.

FIG. 5 is an enlarged schematic plan view showing a part in the vicinityof a corner of a conventional lead frame.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a schematic plan view showing a unit region (a repetition unitcorresponding to a semiconductor device) of a lead frame 1 according toan embodiment of the present invention. The unit region of the leadframe 1 is, for example, substantially in the shape of a square andsubstantially symmetrical in the vertical and horizontal directions inFIG. 1. Therefore, reference numerals are given to only the upper leftquarter part of the unit region in FIG. 1, but each of the remainingquarter parts has the same shape. The unit region comprises a frameportion 2 disposed in the peripheral part, a supporting portion 4 in thecentral part, a hanging lead portion 3 connecting the supporting portion4 and an inner corner portion of the frame portion 2, and lead terminalportion 5 disposed on the inner side of the frame portion 2, andextending in parallel in the vertical and horizontal directions on thehorizontal and verticals sides, respectively. The frame portion 2 isusually provided with holes (not shown) for positioning, fixing and thelike the lead frame 1 in the fabricating process of a semiconductordevice.

The supporting portion 4 extends diagonally from the inner corner of theframe portion 2 through the hanging lead portion 3. In other words, thewhole of the supporting portion 4 is X-shaped. The supporting portion 4is larger in width than the hanging lead portion 3. A step 3 a isprovided in the way of the hanging lead portion 3, and the supportingportion 4 is upset in a higher position than that of the frame portion2.

The lead terminal portions 5 extend from the inner sides of the frameportion 2 toward the center thereof and vertically with respect to theinner sides. The hanging lead portion 3 is oblique with respect to thelongitudinal direction of the lead terminal portions 5 with an angle ofabout 45° in plan view. Each of the lead terminal portions 5 has thesame length.

A plurality of such unit regions each having the abovementionedstructure are disposed in close to one another and constitute a leadframe.

In the process of fabricating a semiconductor device, a semiconductorchip is die-bonded on the supporting portion 4, and electrodes of thesemiconductor chip and the lead terminal portions 5 are connected toeach other by metal wires. Thereafter, the semiconductor chip, thesupporting portion 4, a part of the hanging lead portion 3 and a part ofthe lead terminal portions 5 are covered with a sealing resin and thelead terminal portions 5 and the hanging lead portions 3 are cut at theposition of a cutting line E shown in a broken line. The region coveredwith the sealing resin is a region enclosed by the cutting line E.

FIG. 2 is an enlarged schematic plan view showing a corner part of aunit region of lead frame shown in FIG. 1.

Among the plurality of lead terminal portions 5, each lead terminalportion 5B not adjacent to the hanging lead portion 3 has a head sideformed perpendicular to the length thereof. On the other hand, each leadterminal lead 5A adjacent to the hanging lead portion 3 has an obliquehead side substantially in parallel with and opposed to the side of thehanging lead portion 3 through the whole width of the lead terminalportion 5A. In other words, the lead terminal portion 5A is a chamferedlead terminal portion having, at its head end, a chamfered portionformed substantially in parallel with the hanging lead portion 3 so asto avoid interference with the hanging lead portion 3.

Step portions are provided at the sides of each lead terminal portion 5.That is, the lead terminal portion 5 has two wide portions and twonarrow portions alternately disposed at shifted positions in thelongitudinal direction thereof. As can be seen in FIG. 2 with respect tothe adjacent lead terminal portions 5A and 5B, and is also apparent inFIG. 1 with respect to all adjacent terminal portions 5, the wide andnarrow portions of each adjacent pair of lead terminal portions (such asthe adjacent wide portions at the head ends of the lead terminalportions 5A and 5B) have respective opposing (adjacent) sides which areparallel to each other. The two wide portions and one narrow portion arewholly sealed within the sealing resin, and the remaining narrow portionis partly sealed with the sealing resin. With such a shape, the leadterminal portion 5 is hard to be pulled out toward the peripheral side.

FIG. 3A is a sectional view along the cutting line C-C of FIG. 2 andFIG. 3B is a sectional view along the cutting line D-D of FIG. 2.

The section along the cutting line C-C is a section of the wide portionof the lead terminal portion 5, and is in the shape of an invertedtrapezoid the upper side of which has a length t1 and the lower side ofwhich has a length t2 (t1>t2) (FIG. 3A).

The section along the cutting line D-D is a section of the narrowportion of the lead terminal portion 5, and is in the shape of arectangle having a width t2 (FIG. 3B). That is, the upper surface of thelead terminal portion 5 has different two widths t1 and t2 shifted inthe longitudinal direction, but the bottom surface thereof has the fixedwidth t2.

After sealing the lead frame 1 with a sealing resin, the sealing resinis filled to the position F in the same plane with the bottom surface ofthe lead terminal portion 5, and the bottom surface of the lead terminalportion 5 is exposed from the sealing resin to form a terminal portionfor outer connection (an outer lead portion). At the wide portion havingan inverted trapezoidal section (FIG. 3A), the lead terminal portion 5is wider in the sealing resin and has tapered surfaces opposed to thebottom surface side of the sealing resin. With this structure, the leadterminal portion 5 is hard to be pulled out downwardly from the sealingresin.

Further description will be given with reference to FIG. 2 again.

Since the lead terminal portion 5 functions as a lead for connectionwith outer wiring substrate, the exposed area of the lead terminalportion 5 from the sealing resin must be lager than a predeterminedarea. Therefore, it is necessary to secure more than a predeterminedlength of the lead terminal portion 5 after being cut. On the otherhand, in order to obtain a small-sized semiconductor device, it ispreferable that the length of the lead terminal portion 5 is as short aspossible. From these reasons, the lead terminal portion 5 is formed tohave a predetermined necessary minimum length L1.

The minimum distance between the hanging lead portion 3 and the leadterminal portion 5A adjacent to the hanging lead portion 3 must be largeenough to ensure insulating reliability between them. However, in orderto obtain a small-sized semiconductor device, it is preferable that theminimum distance between them is small. From these reasons, the minimumdistance between them is designed to be a predetermined necessaryminimum distance L2.

When, using a lead terminal portion 53 having a conventional shape shownin FIG. 5, the length of the lead terminal portion 53 is set to be thepredetermined length L1 and the minimum distance between the hanginglead portion 52 and the adjacent lead terminal portion 53 is set to bethe predetermined distance L2, the lead terminal portion 53 must bedisposed further on the peripheral portion side in comparison with thecase of this embodiment. The reason is that, since a corner portion 54of a conventional lead terminal portion 53 at the most adjacent positionto the hanging lead portion 52 protrudes toward the hanging lead portion52, the minimum distance becomes smaller than the predetermined distanceL2 when the head end position A1 is aligned with the head end positionB1 of this embodiment. Therefore, the head end position B1 of the leadterminal portion 5 of this embodiment can be set at a more innerposition by a distance L3 in comparison with the head end position A1 ofthe conventional lead terminal portion 53. Since the lengths of the leadterminal portions 5, 53 are the predetermined length L1 respectively,the rear end position B2 of the lead terminal portion 5 of thisembodiment is at a more inner position in comparison with the rear endposition A2 of the conventional lead terminal portion 53. As a result, aunit region of such a lead frame 1 according to the present inventioncan be small-sized.

Further, since the sealing resin is formed substantially in the sameplane with the rear end positions A2, B2, a semiconductor device using alead frame 1 of this embodiment can be more small-sized by 2×L3 per oneside. Therefore, the packaging area of the semiconductor device can besmaller.

It is also noted that as can be seen in FIG. 2 (as well as in FIG. 1),the respective head sides of the successively adjacent lead terminalportions 5 confronting the semiconductor chip are aligned along astraight line (for example, line B1 in FIG. 2).

FIG. 4 is a schematic sectional view of a semiconductor devicefabricated using such a lead frame 1. Each part of the lead frame 1 isgiven with the same reference numeral as shown in FIG. 1 and thedescription thereof is omitted.

A semiconductor chip 6 is die-bonded on a supporting portion 4. Thesupporting portion 4 is X-shaped (see FIG. 1). The area of the uppersurface of the supporting portion 4 is smaller than that of the bottomsurface of the semiconductor chip 6.

Electrodes formed on the upper surface of the semiconductor chip 6 andthe lead terminal portions 5 are electrically connected to each other bymetal wires 7. The semiconductor chip 6, metal wires 7 and a part of thelead frame 1 are covered with a sealing resin 8. At the bottom surfaceof the semiconductor device, the lead terminal portions 5 and thesealing resin 8 are formed in the same plane, and the bottom surface ofeach lead terminal portion 5 is exposed. The sealing resin 8 is presentbelow the supporting portion 4 by a thickness corresponding to theheight of the upsetting. Further, the end face of the lead terminalportion 5 is substantially in the same plane with the side surface ofthe sealing resin 8.

A semiconductor device having such a structure can be surface-mounted,for example, on a wiring substrate with the lead terminal portions 5exposed at the bottom surface functioning as outer terminals. Further,since only one surface side of the lead terminal portion 5 is sealed bythe sealing resin 8, the thickness of the semiconductor device can bemade smaller. Therefore, such a semiconductor device can be suitablymounted on each kind of thin type apparatus.

The sealing resin 8 is present below the supporting portion 4, andtherefore, the supporting portion 4 and the hanging lead porting 3 arefirmly connected with the sealing resin 8. Since the area of thesupporting portion 4 is smaller than that of the bottom surface of thesemiconductor chip 6, parts of the bottom surface of the semiconductorchip 6 are in direct contact with the sealing resin 8. As a result,exfoliating phenomenon occurring at the boundary surface between thesupporting portion 4 and the semiconductor element 6 can be reduced.

Though one embodiment of the present invention has been described above,the present invention can be embodied in other forms. For example, inthe abovementioned embodiment, a lead terminal portion 5 having the wideportions and the narrow portions, but the lead terminal portion 5 mayhave the same width throughout the length thereof. Further, the wideportion of the lead terminal portion 5 has a section in the shape of aninverted trapezoid in the abovementioned embodiment, but the wideportion may have a rectangular section. Further, the narrow portion ofthe lead terminal portion 5 may have a section in the shape of aninverted trapezoid, and the lead terminal portion 5 may have the samesection in the shape of an inverted trapezoid throughout the lengththereof.

Further, in the abovementioned embodiment, the head end face of the leadterminal portion 5 is in the same plane with the side surface of thesealing resin 8, but the head end face of the lead terminal portion 5may covered with the sealing resin 8. Furthermore, the lead terminalportion 5 may be cut at a position protruding from the sealing resin 8.In this case, since the lead terminal portion 5 can be mounted on awiring substrate or the like at a position protruding from the sealingresin 8, the lower surface of the lead terminal portion 5 need to beexposed from the sealing resin 8.

Further, though the supporting portion 4 on which a semiconductor chip 6is die-bonded is X-shaped in the abovementioned embodiment, thesupporting portion 4 may be in other shapes such as a rectangle.

Further, though the supporting portion 4 is raised in the abovementionedembodiment, the present invention can include such structures that thesupporting portion 4 is in the same plane with the lead terminal portion5 and that the supporting portion 4 is at a position lower than the leadterminal portion 5.

Although the embodiments of the present invention have been describedand illustrated in detail, it is clearly understood that the same is byway of illustration and example only and is not to be taken by way oflimitation, the spirit and scope of the present invention being limitedonly by the terms of the appended claims.

What is claim is:
 1. A semiconductor device, comprising: a semiconductorchip having a plurality of electrodes on a first surface thereof; afirst lead having a supporting portion for mounting the semiconductorchip thereon, and a projecting portion which projects in a firstdirection from the supporting portion; a second lead extending in asecond direction non-parallel with the first direction; one or morethird leads extending in the second direction, such that a lineextending in a third direction perpendicular to the first directionpasses through the second lead and the one or more third leads; aplurality of wires connecting the plurality of electrodes with thesecond lead and the one or more third leads; and a resin covering thesemiconductor chip, the first lead, the second lead, the plurality ofthird leads, and the plurality of wires, wherein the second lead has afirst surface and a side surface, such that one of the plurality ofwires is connected to the second lead on the first surface, wherein thesecond lead includes a first portion and a second portion, the firstportion having a width larger than the second portion, the first portionhaving one side parallel to the first direction, and the first portionlocated between the second portion and the first lead, wherein the sidesurface of the second lead is exposed from the resin, wherein the one ormore third leads each includes a first portion, a second portion, and athird portion, such that the first portion is located between the secondportion and the third portion and has a width greater than the secondportion and the third portion, and wherein the one or more third leadseach includes a first surface and a side surface, such that one of theplurality of wires is connected to the one or more third leads on thefirst surface, wherein the side surface of the third lead is exposedfrom the resin.
 2. The semiconductor device of claim 1, wherein the oneor more third leads includes a plurality of third leads arranged suchthat a line parallel to the second direction intersects each of theplurality of third leads.
 3. The semiconductor device of claim 1,wherein a width in the second direction of the supporting portion of thefirst lead is greater than a width in the second direction of the secondlead, and a width in the third direction of the supporting portion ofthe first lead is greater than a width in the third direction of thesecond lead.
 4. The semiconductor device of claim 1, wherein the one ormore third leads includes a first row of a plurality of third leadsarranged in the second direction and a second row of a plurality ofthird leads arranged in the third direction, a width in the seconddirection of the supporting portion of the first lead is greater than awidth in the second direction of the first row of third leads, and awidth in the third direction of the supporting portion of the first leadis greater than a width in the third direction of the second row ofthird leads.
 5. The semiconductor device of claim 1, wherein the secondlead includes four pairs of second leads arranged at corners of thesupporting portion of the first lead, wherein each second lead of eachpair of second leads is configured such that the one side of the firstportion parallel to the first direction is parallel to the one side ofthe first portion of the other second lead of the pair of second leadsand faces the one side of the first portion of the other second lead ofthe pair of second leads.
 6. The semiconductor device of claim 1,wherein the one or more third leads includes a second surface oppositethe first surface, the first surface of the first portion of the one ormore third leads having a width greater than the second surface of thefirst portion of the one or more third leads.
 7. The semiconductordevice of claim 6, wherein the first surface of the second portion ofthe one or more third leads has a width equal to the second surface ofthe second portion of the one or more third leads.
 8. The semiconductordevice of claim 1, wherein the first portion of the one or more thirdleads has a trapezoidal cross-sectional shape.
 9. The semiconductordevice of claim 1, wherein the one or more third leads includes first,second, third, and fourth rows of a plurality of third leads, whereinthe first and second rows of third leads are symmetrical with respect tothe second direction, and wherein the third and fourth rows of thirdleads are symmetrical with respect to the third direction.
 10. Asemiconductor device, comprising: a semiconductor chip having aplurality of electrodes on a surface thereof; lead terminal portions forexternal connection; a supporting portion on which the semiconductorchip is mounted; hanging lead portions connected to the supportingportion; metal wires for connecting the lead terminal portions and thecorresponding electrodes of the semiconductor chip to each other; and asealing resin for sealing the semiconductor chip and the metal wires insuch a manner that a part of each of the lead terminal portions isexposed, wherein each of the lead terminal portions arranged adjacent tothe hanging lead portions has a first side at a first end closer to thesemiconductor chip, the first side is substantially along an adjacentone of the hanging lead portions, and four pairs of the first sides areplaced across one of the corresponding hanging lead portions.
 11. Thesemiconductor device according to claim 10, wherein a bottom surface ofeach of the lead terminal portions is exposed from a bottom surface ofthe sealing resin.
 12. The semiconductor device according to claim 11,wherein a side face of a second end opposite to the first end of each ofthe lead terminal portions is substantially in a same plane with a sidesurface of the sealing resin.
 13. The semiconductor device according toclaim 12, wherein each of the hanging lead portions extends diagonallyfrom a corner of the supporting portion.
 14. The semiconductor deviceaccording to claim 13, wherein each of the hanging lead portions isoblique with respect to a longitudinal direction of the lead terminalportions with an angle of approximately 45 degree.
 15. The semiconductordevice according to claim 14, wherein the supporting portion includes anoffset so that part of the sealing resin intrudes into a space below thesupporting portion.
 16. The semiconductor device according to claim 15,each of the lead terminal portions arranged adjacent to the hanging leadportion includes a curved side adjacent to the first side.
 17. Thesemiconductor device according to claim 16, wherein the first side andpart of the corresponding one of the hanging lead portions aresubstantially parallel each other.
 18. The semiconductor deviceaccording to claim 17, wherein the supporting portion is larger in widththan each of the hanging lead portions.
 19. The semiconductor deviceaccording to claim 18, wherein at least a part of a section of one ofthe lead terminal portions is in a shape of an inverted trapezoid. 20.The semiconductor device according to claim 18, wherein at least a partof a section of one of the lead terminal portions includes a shorterbottom length than the length of an upper portion of one of the leadterminal portions.